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How FriendFeed uses MySQL to store schema-less data - Bret Taylor's blog
21 Dezembro 2009, 12:23:56 | Visitar
http://bret.appspot.com/entry/how-friendfeed-uses-mysql
Our datastore stores schema-less bags of properties (e.g., JSON objects or Python dictionaries). The only required property of stored entities is id, a 16-byte UUID. The rest of the entity is opaque as far as the datastore is concerned. We can change the "schema" simply by storing new properties. We index data in these entities by storing indexes in separate MySQL tables. If we want to index three properties in each entity, we will have three MySQL tables - one for each index.
